research

Dear sir,



I am modeling ligament structures in the knee joint finite element model
with non-linear springs and I am successfully getting non-linear
displacement curve.



My only problem is with the calculation of tension in the springs. I
have a set of non-linear springs representing a particular ligament in
the joint, which is having an elongation when I apply the forces on the
joint. I am giving pre-load to the springs so that they do not have any
slack in them before the analysis. I am also specifying the stiffness of

The Solution of a Differential Equation or a Set of Differential Equations Converges vers the Exact if it is Consistant and it is Stable : Lax's Theorem. Since the Exact is not always known it is convenient to apply this Theorem. Numerical instabilities are a result of Roundoff errors and Truncation errors. The Domain of Stability can be obtained from a Von Newman analysis in the Complex domain. This implies a condition (relation) between the variation steps. 

Mohammed Lamine 

In this contribution (see http://arxiv.org/abs/1306.4385), we derive lower and upper bounds for Wachspress coordinates over any simple d-dimensional simple convex polytope.  Numerical results for the Poisson equation on nontrivial polyhedral meshes are presented that affirm the linear rate of convergence in the energy seminorm of the polyhedral finite element method.  Matlab code to compute the Wachspress shape functions and its gradient on convex polygonal and polyhedral elements is also provided.

These two papers (with one on beams and the other on plates) have recently been
published online:

http://link.springer.com/article/10.1007/s00033-013-0343-z

http://link.springer.com/article/10.1007/s00707-013-0880-8

hi,

 I am trying to model pullout behaviour in abaqus. i generated my 3d model with the help of texgen and i am applying velocity b.c.s to simulate pullout. I am expecting that NFORC beneath the point of applying velocity will give the pullout load. am i correct?. If not, wat will fetch my query?

if my sum up the reactions at the boundary i may not get the pullout load becoz of the frictional force between the fabric interface.